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 20h comment What happens when Ar and HCl are mixed at 77 K? What if the pressure is very low so that they are each below their equilibrium vapor pressures? 1d comment What happens when Ar and HCl are mixed at 77 K? What’s the pressure? 2d comment What causes negative deviation in a compressibility factor graph: decreased pressure or decreased volume? The explanation should not involve the walls of any container. The state behavior of a gas is independent of interaction with any container. Nov 4 answered Why when deriving the Clapeyron equation can you assume that dH = dq, as surely the pressure is not constant? Oct 30 comment Is it possible to use the laws of termodynamics for non-ideal systems? Yes, this can be done, at least up to moderate pressures like these if you know the 2nd virial coefficients for the pure gases. You need to learn how to get the residual properties of gas mixtures at elevated pressures. This is all explained in chapters 10-15 of Introduction to Chemical Engineering Thermodynamics by Smith and van Ness. Do you at least know the mole fractions of the reactant and product mixtures? Oct 22 comment During solid-solid phase transition, if both solid phases are incompressible, is ΔG independent of p? There is no mistake. $\Delta G$ does depend on the pressure, even for incompressible solids. Google "Poynting effect." Oct 19 answered Clarification on the Clausius inequality Oct 18 answered Thermodynamic statements Oct 15 revised Is enthalpy of combustion the 'heat released' or 'enthalpy change'? deleted 35 characters in body Oct 15 answered Is enthalpy of combustion the 'heat released' or 'enthalpy change'? Oct 11 comment Is it really possible for a liquid to stay afloat a gas (vapor)? The critical temperature of CO2 is 35C. Above this temperature, no matter high the pressure, CO2 can't be liquified. So it is certainly possible to find a pressure where its density is higher than that of water. Oct 10 answered Work done in cyclic process Oct 9 comment Heat exchange in adiabatic process For an ideal gas, the equation for the work in your original post is correct. However, you can't really use it unless you know the final pressure and volume. The final conditions depend on the details of how the process is carried out. Oct 9 answered Heat exchange in adiabatic process Oct 9 comment Heat exchange in adiabatic process The above equation does not say that the work done when a system is given heat at constant volume equals $nC_v\Delta T$. The relationship is not equal to the heat transferred. It is equal to the change in internal energy. Did you think that the only way the temperature of a gas can change is by adding or removing heat? Oct 8 answered Why Gibbs energy change of a process can be negative at constant temperature and pressure? Oct 8 comment What is the true meaning of Gibbs energy and chemical potential? I understand it as the partial derivative of the total Gibbs free energy with respect to the number of moles of the given species holding the number of moles of all other species (and T and P) constant. Oct 8 comment What is the true meaning of Gibbs energy and chemical potential? Your equation gives the chemical potential of a species in a gas mixture at a partial pressure of $p_A$ bars in the mixture. In this equation, $\mu^o_A$ is the molar free energy of the pure species at 1 bar and at the same temperature. Oct 6 comment What are D_b and D_a in the Generalized Fugacity Coefficients table? See page 574 in your book. Oct 5 comment What are D_b and D_a in the Generalized Fugacity Coefficients table? Have you checked the text in the book?